Quality of Service is an important attribute of a software system. In retrospect, performance assessment based on user interaction with the system has given a better understanding of underlying disciplines of the prod...Quality of Service is an important attribute of a software system. In retrospect, performance assessment based on user interaction with the system has given a better understanding of underlying disciplines of the product. In this paper, we capture user interaction with the prototype/User Interface (UI). An approach for developing activity model from the user interface model is presented using workflows and functional elements. A methodology is proposed to transform UI into activity diagram. The approach is validated by an experimental setup using Amazon service. The performance of Amazon service is assessed using activity based performance prediction methodology, and the simulation results are obtained using SMTQA.展开更多
The perforated stiffened panel is generally found as a sub-component of sophisticated structures.The fundamental purpose of this panel is to withstand against buckling under complicated loading and environmental condi...The perforated stiffened panel is generally found as a sub-component of sophisticated structures.The fundamental purpose of this panel is to withstand against buckling under complicated loading and environmental conditions.Hence,an accurate knowledge of critical buckling behaviour of stiffened panels is very much essential for a reliable and lightweight structural design.In this paper,the focus is on quasi-laminated panels with different cutout shapes of various sizes and their responses to hygrothermal environments under nonlinearly varying edge loads and is compared with the locally stiffened panels.Towards this,the modelling of the panel and stiffener is done by adopting nine-noded heterosis plate elements and three noded beam elements respectively.The stiffener formulation is suitably modified in order to take the torsional effect also into consideration along with the effect of shear deformation.Initially,the plate and the stiffener elements are treated separately,and then the displacement compatibility is maintained between them by using the transformation matrix.For a given loading and geometric discontinuity,the stress distribution within the perforated panel is highly non-uniform in nature and hence a dynamic approach has been used to calculate buckling loads by adopting two sets of boundary conditions,one set for pre-buckling stress analysis and the second set for buckling analysis.Four different quasi-isotropic stacking sequences are deliberated in this work by varying different ply-orientation in each scheme.The study also addresses the effect of various parameters such as nonlinear loads,hygro-thermal loads,cutout size and shapes,position of cutout,stiffener parameters,stacking sequences,thickness of plate and boundary conditions.展开更多
Mg alloys are emerging as potential and very promising alternatives for replacing permanent metallic implant materials such as steels and titanium in applications where the implants need to be removed following healin...Mg alloys are emerging as potential and very promising alternatives for replacing permanent metallic implant materials such as steels and titanium in applications where the implants need to be removed following healing through revision surgery.Use of Mg alloys for implant application is seen as a game changer and Mg alloys are almost perfect materials for the future in both engineering and biomedical applications.Present review therefore focuses on highlighting significance of Mg alloys in biomedical field and risks of using permanent metallic implants particularly when the implants are no longer required after the injury is healed.In this review,importance of orthopedic implants in present scenario,serious concern related to accidents that are causing permanent disabilities,demand in orthopedic implant market worldwide,potential applications of Mg based materials and their compatibility in biological environment is presented and discussed.In addition,degradation rate,major reactions associated with Mg based materials and effect of alloying elements on implant performance are also discussed based on in-vivo results.Recent advances in development of Mg alloys through various techniques and their performance in in-vitro conditions are also outlined.Possible ways to eliminate the limitations of Mg alloys include alloying,melt purification,surface alterations,surface modifications,chemical treatment,secondary processing etc.are discussed.Challenges and opportunities for Mg alloys to become ideal implant material is also addressed.展开更多
The present study focuses on the synthesis and characterization of lanthanum(La^(3+))-doped calcium nanoferrites(CaLa_(x)Fe_(2-x)O_(4):x=0.025,0.050,0.075 and 0.100)using the sonochemical method.Various techniques wer...The present study focuses on the synthesis and characterization of lanthanum(La^(3+))-doped calcium nanoferrites(CaLa_(x)Fe_(2-x)O_(4):x=0.025,0.050,0.075 and 0.100)using the sonochemical method.Various techniques were employed to analyze the effect of La^(3+)infusion,Raman spectroscopy confirms the presence of active A_(1g),T_(2g)and E_g modes in the CaLa_(x)Fe_(2-x)O_(4)nanoferrite,indicating the formation of an active ferrite system.The introduction of La^(3+)doping results in a significant increase in the band gap energy,rendering the nanoferrites insulating(3.23-3,57 eV).At higher frequencies,the impedance studies reveal minimal losses and better AC conductivity,pointing to improved dielectric characteristics.At higher frequencies,the Q-factor of La-doped calcium nanoferrites shows lower electromagnetic losses.The M-H curve exhibits ferromagnetic behavior,with La^(3+)-doped calcium nano ferrites displaying a saturation magnetization ranging from 12.72 to 18.10 emu/g.The incorporation of La^(3+)also induces enhanced electrical polarization,leading to notable dielectric loss and increased absorption of electromagnetic waves.Consequently,these CaLa_(x)Fe_(2-x)O_(4)nanoferrites demonstrate potential as effective microwave absorbers across a wide frequency range,with significant shielding absorption observed at 8.8-9.1 GHz.展开更多
Wireless Body Area Network (WBAN) technology has significantly increased the potential of remote healthcare monitoring systems. The devices used for WBAN have limited energy resources. For most devices it is impossibl...Wireless Body Area Network (WBAN) technology has significantly increased the potential of remote healthcare monitoring systems. The devices used for WBAN have limited energy resources. For most devices it is impossible to recharge or change the batteries. Since the data mostly consists of medical information, high reliability and low delay is required. The main objective of this simulation study is to evaluate the performance of routing protocol on static IEEE 802.15.4 to determine the most suitable routing protocol for Wireless Body Area Networks. Here, investigations on the various routing protocol suggest cluster topology and AODV as the probable candidate. About 16% improvement in the energy consumption was observed when modifications were made considering the energy and mobility, thus achieving high residual battery capacity and eliminating the need for recharging the batteries.展开更多
This paper aims to examine the influence of thermal radiation on magnetohydrodynamics(MHD)convective two-phase flows through the asymmetric divergent channel under first-order velocity and thermal slip conditions.Suit...This paper aims to examine the influence of thermal radiation on magnetohydrodynamics(MHD)convective two-phase flows through the asymmetric divergent channel under first-order velocity and thermal slip conditions.Suitable transformations are used to nondimensionalize the governed partial differential equations and then solved them numerically.A grid-independent test is done to check the consistency of the numerical method and then validated with existing published results in a limiting case.The graphical illustrations are provided to explain the impacts of various emerging parameters on flow fields.An enhancement in particle velocity is observed with an increment in the velocity slip parameter.As the temperature slip parameter improves a decrement in the fluid as well as particle temperature is observed.An increment in radiation parameter augments fluid temperature.This type of flow has multifarious range applications like fluidized beds,gas cooling systems,polishing heart valves and internal cavities,etc.展开更多
文摘Quality of Service is an important attribute of a software system. In retrospect, performance assessment based on user interaction with the system has given a better understanding of underlying disciplines of the product. In this paper, we capture user interaction with the prototype/User Interface (UI). An approach for developing activity model from the user interface model is presented using workflows and functional elements. A methodology is proposed to transform UI into activity diagram. The approach is validated by an experimental setup using Amazon service. The performance of Amazon service is assessed using activity based performance prediction methodology, and the simulation results are obtained using SMTQA.
文摘The perforated stiffened panel is generally found as a sub-component of sophisticated structures.The fundamental purpose of this panel is to withstand against buckling under complicated loading and environmental conditions.Hence,an accurate knowledge of critical buckling behaviour of stiffened panels is very much essential for a reliable and lightweight structural design.In this paper,the focus is on quasi-laminated panels with different cutout shapes of various sizes and their responses to hygrothermal environments under nonlinearly varying edge loads and is compared with the locally stiffened panels.Towards this,the modelling of the panel and stiffener is done by adopting nine-noded heterosis plate elements and three noded beam elements respectively.The stiffener formulation is suitably modified in order to take the torsional effect also into consideration along with the effect of shear deformation.Initially,the plate and the stiffener elements are treated separately,and then the displacement compatibility is maintained between them by using the transformation matrix.For a given loading and geometric discontinuity,the stress distribution within the perforated panel is highly non-uniform in nature and hence a dynamic approach has been used to calculate buckling loads by adopting two sets of boundary conditions,one set for pre-buckling stress analysis and the second set for buckling analysis.Four different quasi-isotropic stacking sequences are deliberated in this work by varying different ply-orientation in each scheme.The study also addresses the effect of various parameters such as nonlinear loads,hygro-thermal loads,cutout size and shapes,position of cutout,stiffener parameters,stacking sequences,thickness of plate and boundary conditions.
文摘Mg alloys are emerging as potential and very promising alternatives for replacing permanent metallic implant materials such as steels and titanium in applications where the implants need to be removed following healing through revision surgery.Use of Mg alloys for implant application is seen as a game changer and Mg alloys are almost perfect materials for the future in both engineering and biomedical applications.Present review therefore focuses on highlighting significance of Mg alloys in biomedical field and risks of using permanent metallic implants particularly when the implants are no longer required after the injury is healed.In this review,importance of orthopedic implants in present scenario,serious concern related to accidents that are causing permanent disabilities,demand in orthopedic implant market worldwide,potential applications of Mg based materials and their compatibility in biological environment is presented and discussed.In addition,degradation rate,major reactions associated with Mg based materials and effect of alloying elements on implant performance are also discussed based on in-vivo results.Recent advances in development of Mg alloys through various techniques and their performance in in-vitro conditions are also outlined.Possible ways to eliminate the limitations of Mg alloys include alloying,melt purification,surface alterations,surface modifications,chemical treatment,secondary processing etc.are discussed.Challenges and opportunities for Mg alloys to become ideal implant material is also addressed.
基金Project supported by the Strategic Academic Leadership Program of the Southern Federal University(Priority 2030)。
文摘The present study focuses on the synthesis and characterization of lanthanum(La^(3+))-doped calcium nanoferrites(CaLa_(x)Fe_(2-x)O_(4):x=0.025,0.050,0.075 and 0.100)using the sonochemical method.Various techniques were employed to analyze the effect of La^(3+)infusion,Raman spectroscopy confirms the presence of active A_(1g),T_(2g)and E_g modes in the CaLa_(x)Fe_(2-x)O_(4)nanoferrite,indicating the formation of an active ferrite system.The introduction of La^(3+)doping results in a significant increase in the band gap energy,rendering the nanoferrites insulating(3.23-3,57 eV).At higher frequencies,the impedance studies reveal minimal losses and better AC conductivity,pointing to improved dielectric characteristics.At higher frequencies,the Q-factor of La-doped calcium nanoferrites shows lower electromagnetic losses.The M-H curve exhibits ferromagnetic behavior,with La^(3+)-doped calcium nano ferrites displaying a saturation magnetization ranging from 12.72 to 18.10 emu/g.The incorporation of La^(3+)also induces enhanced electrical polarization,leading to notable dielectric loss and increased absorption of electromagnetic waves.Consequently,these CaLa_(x)Fe_(2-x)O_(4)nanoferrites demonstrate potential as effective microwave absorbers across a wide frequency range,with significant shielding absorption observed at 8.8-9.1 GHz.
文摘Wireless Body Area Network (WBAN) technology has significantly increased the potential of remote healthcare monitoring systems. The devices used for WBAN have limited energy resources. For most devices it is impossible to recharge or change the batteries. Since the data mostly consists of medical information, high reliability and low delay is required. The main objective of this simulation study is to evaluate the performance of routing protocol on static IEEE 802.15.4 to determine the most suitable routing protocol for Wireless Body Area Networks. Here, investigations on the various routing protocol suggest cluster topology and AODV as the probable candidate. About 16% improvement in the energy consumption was observed when modifications were made considering the energy and mobility, thus achieving high residual battery capacity and eliminating the need for recharging the batteries.
文摘This paper aims to examine the influence of thermal radiation on magnetohydrodynamics(MHD)convective two-phase flows through the asymmetric divergent channel under first-order velocity and thermal slip conditions.Suitable transformations are used to nondimensionalize the governed partial differential equations and then solved them numerically.A grid-independent test is done to check the consistency of the numerical method and then validated with existing published results in a limiting case.The graphical illustrations are provided to explain the impacts of various emerging parameters on flow fields.An enhancement in particle velocity is observed with an increment in the velocity slip parameter.As the temperature slip parameter improves a decrement in the fluid as well as particle temperature is observed.An increment in radiation parameter augments fluid temperature.This type of flow has multifarious range applications like fluidized beds,gas cooling systems,polishing heart valves and internal cavities,etc.